Method of treating milk.



EWRHLKELE CG C. H. CAMPBELL.

METHOD OF TREATING MILK.

APPLICATION man JULY 25.1913.

Patented Apr. 3, 1917.

3 SHEETS-SHEET I.

mmmw.

WITNESSES: 71

C. H. CAMPBELL.

METHOD OF TREATING MILK.

Patented Apr. 3, 1917 APPLICATION FILED lULY 25 1913- 3 SHEETS-SHEET 2.

INVENTOR B17 ttm'new, V 6mm QM WITNESSES:

GHARILEfi H, CAMPBELL, 0]? NEW YORK, Y., ASSIGNOR, BY MESNE ASSIGNMENTE, 1'0 EORDENS UDNDEIISED MILE CQMPANI, OF NEW YORK, 22; A CORPORATIDN OF new JERSEY.

earner.

To all whom it may concern:

Be it known that 1, CHARLES H. CAMP- BELL, a citizen of the United States, residing in the borough of Manhattan, city, county, and State of New-York, have invented a certain newand useful Method of Treating Milk; of which the following is a specification.

This invention relates to'the art of heattreating milk, and is peculiarly adapted to the treatment which requires the elimination or neutralization of the heat units added in effecting certain desired results, as for instance in the evaporation, or in the pasteurization, of milk, which I have, discovered requires that the milk under treatment be raised to a given uniform temperature throughout the entire mass under-treatment as rapidly as possible, and without delay cooled uniformly throughout this entire mass rapidly. In some methods, now in use, of treatin milk in which bacteria and pathologica germs develop rapidly at certain temperatures, .it has been found that during the interval elapsing between the heating and the cooling, and also the time elapsing to elimimate the heat units from the entire mass, the

ideal conditions for development of bacteria and germs persist for a suflicient length of time to permit propagation to an extent which will practically render m! the eti'ects sought to be attained by the treatment. In

' aeciable the present improvement the milk under treatment is quickly, aml'uniformly throughout the mass, brought to the desired temperature, maintained at that temperature for.

the required length of time, and without an interval of time 'elapsing,

quickly, and uniformly throughout the entire mass, cooled to the desired temperature.

' This is all accomplished within the same vessel by the procedures hereinafter described. f The results sought to be accomplishedby certain heat treatments of milk are hastened,

and the product improved by aeration. The

present improvement makes provision for the aeration of the milk at the same. time it is being heated and being cooled, either with air at atmospheric temperature, or with air heated and cooled for these steps respec- .tively.

Specification of Letters I'atent.

METHOD OF TREATING MILK.

Patented Apr. a, rear:

Application filed July 25, 1913. Serial No. 781,081.

elevation of the instal- I Fig". 2 is an enlarged side elevation of portionsof the mechanism illustrated in Fig. 1, certain parts bemgbroken away, and other portions in section for the better disclosure thereof;

Fig. 3 is an end elevation taken on a plane at about the line 3-3 of Fig. 2 looking in the direction ofthe arrow. l

Fig. lis across-section taken on aplane at about the line -l-l of Fig. fldooking in the direction of the arrow;

Fig. 5- is a top view, partly plan and partly'horizontal section, of the structure shown in Fig. 2; and r Fig. 6 is a longitudinal section of the agitator shaft. v

The milk under treatment iseontained' in a. vessel 7, or treating chamber, This vessel is providedwitha jacket space 8 which is located between the walls of the vessel. 7 and thejacket walls 9. During the. treatment of the milk it is agitated. For" the purpose of agitation and themore quick response to the heating and cooling, the agi tators will be heated and cooled. T ewcylin d'ricalagitator shaft 10 is shown extending from end to end of the vessel 7, which vessel is illustrated with a semi-circular bottom and of elongatedform. Theshaft'10 is shown horizontally disposed. at parti-- tion 11 extendsfroin end to-end of thehollow shaft. Reference may be made toIFig. 6, which shows this shaft by itself. The

inlet side 12 of the shaft. is closed-at the far end '13, andthejoutletside 1.4 of the shaft is closed at the end. 15 adjacentkthe inlet end.' The shaftis mounted for-rotation.

The agitators, Whichare of the well known thinmetal shell type in the form of disks 16, are shown elliptical in their section longitudinally of the shaft. The agitator disks are hollow, thus enabling them to act as liquid containers, and each is provided with means of communication to both sides of the shaft partition, that is, each interior communicates with the supply and the exhaust sides .12 and 14: respectively. The connection with the supply side is shown as a conduit in the form of a pipe 17 extending ashort distance into the shaft and a short distance, in. the present instance a little-greater distance, into the interior of the agitator. The conduit for the exhaust is shown in the form of a tube 18 extending a. substantially similar distance into the exhaust side of the hollow shaft, and a shorter distance. into the interior of the agitator. These conduits are shown substantially diametrically disposed. When the exhaust from the, exhaust side 1- is open and liquid is supplied to the supply side 12, it will flow uniformly into all the" agitator disks, filling these and flowing out at the opposite" side. By a proper regulation of the area of opening into and from the disks in respect of the area of the passages 12 and 14, and of means of supplying and exhausting, all the agitators will be of uniform temperature.

WVhen it is desired to entirely discharge liquid which is within the agitators, either for the purpose of emptying them to discontinue the use of the apparatus or for the purpose of changing the liquid which is employed, a dipper 19 is associated with each of the outlet conduits 18, so that upon the rotation of the agitator disks the dipper will collect the remnants of the liquid within the agitator and direct these into the exhaust or discharge conduit 18.

The supply for the agitators is shown controlled by some suitable pump 20 which will pump the liquid past the T 21 through the pipe 22 and into the chamber 23 which surrounds the supply end of the shaft 10. The chamber is so located that the opening to the supply side 12 is at all times free to receive the liquid. The liquid, preferably hot Waterifor the heat treatment, will be pumped in sueh volumes as may be demanded and pass'into the supply side 12, and through the various supply conduits 17 into the agitators. The agitators will thus be supplied in unison and each with water which has not been used in the other agitators, thereby raising them all uniformly throughout the'entire series, to the sa ne temperature. The water will exhaust through the conduits 18 into the exhaust side 14 and flow into the chamber 24 surrounding the exhaust end of the shaft 10, T 25 and pipe 25' and into the discharging nozzle 26. This discharging nozzle is capable of oscillation, so that when the hot water which is being employed may be'discharged into the hot water tank 27 for reuse, and when cold water is being used the nozzle 26 will be swung into such a position that the water will be discharged into a cold water tank 28 for reuse.

The hot water tank is shown provided with a conduit 29 controlled by a valve 30, and the cold water tank is'shown provided with a conduit 31 controlled by a valv 3-3 which connects .by conduits 33 and 34 respectively with a conduit 35 leading through a valve 36 to a connecting conduit 37 which runs into the supply pipe 38 of the pump 20. By this means the water from the tanks 27 and 28 may be selectively drawn through the pump and passed through the agitators and discharged into either of ti tanks as desired.

The water for the jacket space 8 will be led from the pump 20 through the conduit 39 past' the valve 40, and may also be led from the discharge chamber 24 by means of the conduit #11 past the T l2 and valve 43 to the conduit 44 and into the jacket space. A discharge for the water is pro vided for preventin undue pressure within the jacket. Such ischarge in the present instance comprises a pipe 45. see Fig. 4, which pi e leads to some suitable waste not shown. Ihis pipe has a connection at -16 with the upper portion of the jacket space. It also has a connection 47 with the lower portion through the valve 48, and has a connection -19 through the valve 50 at an intermediate point. This intermediate connection is for the urpose of maintaining the jacket partly filled with water as occasion may demand. y

The temperature of the water in the jacket may be maintained by pumping, the hot water into it, or it may be maintained by a supply of steam, An exhaust steam connection is shown at 51 entering the lower portion-of the acket past a suitable controlling device 52, also at 51' entering conduit 44. A live steam supply is also illustrated at 53 having a connection 54 into the supply 38 for the pump, and a connection 56 into the chamber 8, so that the heat of live steam may be directly applied to the milk under treatment if occasion may demand, as for example, if a coagulated or cooked product is desired.

Under some circumstances it is found dcsirable to connect the various portions of the apparatus directly with the city water supply, and for this purpose a connection 57 is provided which connects with the live steam connections under control of the valve 57', so that the water may be caused to pass to the jacket and to the treating vessel 7, or any of these as occasion may demand, bythe proper manipulation of the valves in this systcm of iping.

In certain treatment o1 the milk it is desirable that the milk be aerated during its heating and during its cooling. Purified air is an efiicient med um for the aeration, and

manoea the present description air will be mentioned. At the top-of the chamber 7 on each side there is shown an air chamber 60.

These air chambers are provided with con nections 61 to which downwardly directed nozzles 62 areconnected. These nozzles are shown extending to a point near the bottom of the vessel 7 and substantially beneath the agitator shaft 10. In the present illustration the nozzles are disposed between ad-- jacent agitator disks, and alternately on opposite sides, so that a considerable amount of agitation of the milk is produced by the air discharged through the nozzles. The air is'shown supplied to the chambers 60 from'a blowei' 63 which draws air by means of a conduit 64 through a filtering device 65 and discharges into the chambers 60 through its discharge conduits 66.

A cover 7 is provided for the vessel 7, which cover fits down upon the top of the vessel with a substantially air-tight joint.

It is'shown. provided with a flange 68 resting upon a packing 69 interposed'betwe'eu the flange and the top wall of the chamber 60. The air is preferably exhausted from within the cover- 67 by means of a fan 70 having a connection 71 with the end of the cover 67 and a discharge spout 72.

A suitable gage or the contents of the, yessel is shown at 7. .(Fig. 3).

The contents of the 'vessel 7 will be drained ofi at some suitable point centrally located. A. discharge is shown at 74: controlled by a suitablevalve '75.

The main driving shaft of the machine portions of the milk will at times adhere to the surfacesof the agitators, thereby acting as insulators anddecreasing the -'efli ciency thereof. A convenient form ;of scraper for keeping the surfaces free from" this accumulation is illustrated ,in Fig. 2,,

and comprises a pair of wooden legs -79 shown pivoted together at 80. These legs conform substantiall to the contour of the agitators, and are he d in engagement there- ,with by means of a suitable extension spring 81 connected to the extending ends 82 of the legs 7 9. Thus the scrapers are held to their work yieldingly by the elastically yieldable-connection 81. The scrapers may be readily removed for the purpose of cleansingor when they are not needed, and may be as readily placed in position. The

through the discharge conduits the cold water is caused to circulate. At this discharged into the-cold'water tank 28".

scrapers are shown held in osition by means of a pair of longitudinal y disposed bars 83 and cross bars 84.. i I v 3 The improved method will be carried out withthe present mechanism in substantially the following manner: The milk to be treated will be placed; in the vessel 7. Hot water will be drawn by means of the ump 20 through the connection 39, and null be pumped past the T 21 into the chamber 33, and be caused to pass from the supply side 12 of the hollow longitudinally divided shaft 10 through the conduitsfll7 into the various agitators so as to charge them as required. From these agitators it will pass 18 intothe 1 discharge side of the said shaft 14, and from such shaft into the chamber 24, and from there past T 25 and through conduit 41, valve 43, conduit 44 and into the. jacket space 8, and from such jacketspace back to the pump by conduit 3!) past valve 40 to conduit I 38. If it is desired to raise the temperature beyond that produced by the circulation of the water in the jacket, exhaust steamwill be admitted from the supply 51 by opening the valve 52, and if further elevation oi temperature is desired, the live steam will be admitted by the connection 54. If the milk requires to be broughtto-a still higher tenr perature than that alforded by means of the jacket and the agitators, live steam may be admitted by means of the connection'56 directlv to the milk in the vessel 7.

After the milk has been treated for a suliicient length of time to bring it to the desired temperature, and maintained for a suitable time at that temperature, the supply to the pump 20 will be shut off at valve40 and the water ermitted to exhaust from the agitators. he water will be drawn from the jacket and discharged through the pipe 45, and cold water will then bedrawn from the tank 28 into the pump 20 by opening valves 36 and-32 and closing valve 43, whereupon time, however, the nozzle 26 will be preferably turned so that lillGyCOld water will be Inpractising thismethod, the. entire mass be un'iiormly' brought to the desired temperature rapidly, because the jacket will be of uniform temperature throughout, and the 'ofmilk-under treatment in the vessel 7 will units rapidly removed and be brought down to the safetemperature. By this means injurious results which are liable' to ensue if milk is permitted to remain at cer ain warm temperatures will be avoided, and the product willfbe that which is sought to be obtained. I

Although but one form of apparatus has been described,-yet it will be apparent that changes may be made in the method and in the apparatus within the scope of the claims, without departing from the spirit of the invention. I

I am aware that prior to my invention it has been sought to satisfactorily lower, or

otherwise vary the temperature of milk, in

rotating containers; but none of such prior devices do I regard as comprising my invention, or as covered by my herein made claims, for the reasons, among others, that in all such prior cases in which liquid has been relied upon as the tempering medium, its course, location and distribution relativel to the body of milk treated have been sue as to initiate the tempering proximate to one extremity of such body, and to continue it progressively toward the meanwhile comparatively tempered opposite extremity, thus permitting undue duration, in some parts,

' of temperatures favorable to development of malign bacteria or germs, whereby the final product has been injured or ruined; whereas in those cases in which steam has, as aforesaid, beenused as the heating medium, the height and uncontrollability of its temperatures have, notwithstanding their steril i zing effects, proved, I believe, prohibitory in industrial pasteurization, evaporation, concentration, condensation, or drying of milk, owing to'resultant scalding, burning, coagulation or other injury of the product the fact being that milk cannot be treated at temperatures of 212 F. or higher, without, for many purposes, undesirably or prohibitively changing the character propertiesan d behavior of more, or less, of'its constituents.

By my aforesaid method, however, I not only employ, as the tempering medium, an agent, i. e. a liquid, preferably water, the stability and controllability of whose temperatui 1 is, I have found, unrivaled for the purpose, but that agent is for the first time, as I believe, applied in sucha continuous,

copious and uniform stream, and so subdivided, located, and directed within the body 'of milk treated, as to prevent, in'any region of such body more than another, such duration of transition temperatures as might admit of harmful propagation of undesired germs and bacteria in the milk. By transition temperatures, I mean those through which the milk must 185 while being tempered by any method, and certain of which are, as is well known, favorable to such propagations. By my method, I am enabled to raise or lower the temperature of the body of milk so rapidly and so uniformly throughout all parts of the mass at once, that the transition temperatures are left nowhere long enough to be substantially injurious, the entire body of my milk being, as it were, simultaneously flashed from one sanitary and unpropagative temperature to another, and so rapidly as to preclude the noxious duration proximate to anyextremity, or in any region, more than another of said body, of any temperatures favorable to propagation of undesired germs or bacteria in the milk. My method is particularly important and successful in chilling heated milk down to temperatures of sterility. My simultaneous agitation of the milk, 11. 6. its impulsion to move constantly relatively to the stream of tempering liquid is also of great assistance in speeding and equalizing the changes of temperature. Likewise the constant immediate removal from the disks of thereto-adherent thickened portions of the milk, while in, or rising from and still closely ad'acent to, the latter and their consequent li eration and return to the latter with minimum exposure to the air, are practically indispensable to the successful practice of my method.

Moreover, the effecting of such removals by' means which are not only yielding, but also provided with members, the operative surfaces of whichare, like those of milksoaked wood for example, more yielding and resilient and less temperature-comb:ctive than those of the disks, is of equal importance because I am thereby enabled to not only more thoroughly and eflectively remove the adhesions from the disks, but also to diminish risk of over-heating, and particularly also mechanical injury to milk constituents, as for example, such crushing or bursting of the butter-fat globules as results in their smearing with consequent well known promotion of sourness or rancidity in. the final product, etc.

The products of my process are not only sufficiently sterile as regards germs and bacteria, but free from their even temporarily occasioned malign effects, and when desired, as for pasteurized, evaporated, concentrated, condensed, or even finally dried, products, may, by aid of myiprocedure, be made to retain all of the constituents of the milk in their normal state, except as regards percentage of therewith associated water, and thus the flavor and peptogenic effects of the natural milk.

' I claim as my invention 1. The method of treating a body of milk which POIDPIlSPS raising and maintaining its temperature above normal by aid of heat trausterrml thereto from a therewith contacting rigid surface, and simultaneously, at frequently repeated, equally-timed-apart intervals, under cover of the milk, wiping from. said surface therewith contacting or adhering thickening milk.

2. The method of treating a body of milk which comprises raising and maintaining its temperature above normal by aid of heat transferred thereto from a therewith contacting surface, and simultaneously, at frethe milk timely separated therefrom, and re- I turned to the interior of said body, without being unduly exposed to atmosphere and without being coagulated, burned, or injuriously frictioned or compressed.

In witness wli'ereof,I have hereunto signed my name in the presence of two subscribing Witnesses.

CHARLES H. OAMPBELL.

Witnesses CHAS. LYON RUSSELL, FRED WHITE. 

